Improvement in steam-generators



' UNITED STATES PATENT OFFICE.

EBENEZER DANFORD, OF GENEVA, ILLINOIS.

IMPROVEMENT .IN STEAM-GENERATORS.

Specification formingpart of Letters Patent No. 51,026, dated November21, 1865.

To all whom it may concern:

Be it known that I, EBENEZER DANEORD, of Geneva, in the county of Kaneand State of Illinois, have invented new and useful Improvements in theGeneration of Superheated Steam and I do hereby declare thev followingto be a full, clear, and exact description of the nature, construction,and operation of the same, sufficient to enable one skilled in the artto which it appertains to construct and use the same, reference beinghad to the accompanying drawings, which make part of this specification.

In the usual mode of making steam thereintervenes between the metallicsurface on which theltire acts and the volume of steam in the boiler abody of water which receives the heat transmitted 5 and when steam ismade under these circumstances it is, when of the same pressure, alwaysof the same temperature. Ihus steam of fifty pounds pressure is alwaysof 2810 temperature, and steam of one hundred pounds pressureis alwaysof 327.80 temperature, (Itegnault, Bournes Steam-Engine,) and tablesprepared for the purpose state what are the temperatures of steam ofvarious pressures when so made. Steam so formed may be called naturalsteam.77 Steam so formed admits of being heated by being subjected tothe action of heat of adequate temperature without the presence of waterto take up the heat. Steam so heated is superheated, and is calledsuperheated steam. v

In all the processes for` producing superheated steam heretofore madeuse of, so far as known to me, natural steam is first made, and thenthat steam is made superheated steam by being subjected byitself to theaction of heat, as in the use of steam-chimneys and similarcombinations, whereby natural steam is subjected to the action of heatalter it has passed from the chamber or coil in which it is generated,or after it has passed the point at which the water was converted intosteam.

There have been attempts made to produce steam instantaneously byinjecting water on the inside surface of a Vheated generator,77 (socalled,) the object being the production of natural steamintermittently, as required by the engine, all of which, as far as knownto me, have been failures. Another attempt to produce an economicaleffect in this direction, consisted in the injection of water intosuperheated steam of such a volume that a saturated or wet steam was theproduct, which was afterward conducted over a heated surface to producesuperheated steam.

In my invention the relation between the volume of superheated steam andthe injected water is such that the incoming water is converted intosuperheated steam. The combinations which I have invented for thispurpose are repre ented in drawings hereto annexed, and markedFigures1,2,3,4, 5,and 6, and consist of, first, the vessel A, which I termgenerator, second, the pipe or coil c c c, third, the injector orforce-pump G; fourth, the discharge-pipe D; fth,the steam-pipe S, whosecharacter, operations and purposes are fully and correctly described asfollows:

Figure lis a vertical central section on the line a: a2, Fig. 2. Fig. 2is a horizontal central section on the line x x, Fig. l. Fig. 3 isavertical central section on the line a. b, Fig. 4. Fig. 4 is ahorizontal central section on the line ze', Fig. 3. Fig. 5 is a verticalcentral section on the line c d, Fig. 6. Fig. 6 isa horizontal sectionon the line y y, Fig. 5.

A is a spherical vessel, of such thickness of sides as will furnishadequate strength, and such internal diameter as will furnish the volume of superheated steam required, as here inafter set forth. Thisvessel is placed in a suitable furnace, B, the re and heat ofwhich acton the exterior surface of the vessel. A small quantity of water, beingplaced in the vessel A when it is under the action of heat,

will yield as much natural steam as the capacity of the vessel willpermit at a determinate temperature. The water not converted intonatural steam (because there is no room for any more natural steam ofthat pressure) is to be blown out of the vessel through thedischarge-pipe D by opening the cock H. The continued application ofheat to the natural steam so made will convert it into superheatedsteam, and the vessel will be full of superheated steam, and the volumeofsu perheated steam will be the means of converting water intosuperheated steam, when water is forced into it in the mannerhereinafter described.

C, Figs. 1 and 2, is a pipe or pipes, or coil of pipes, which (incombination, as represented by Figs. 1 and 2) extend to about thecentral part of the generator A, and having on it numerous orifices, thegreater number being near vthe end of the pipes or coil. Through thispipe or coil, and out of these orifices m m m,

. water is forced in jets into the superheated steam. The pipe or coilC, bein gsurrounded by superheated steam, will partake of its heat, andthe water in the pipe or coil will thereby be heated, and the length ofthe pipe or coil C is such that by the time the Water issues from thepipe into the superheated steam it is of nearly the same temperature asthat of the superheated steam. Under these circumstances the enteringwater, regulated in quantity by the engineer, is converted intosuperheated steam immediately.

C' C C', Figs. 3 and 4, are pipes which (in combination representedinFigs. 3 and 4 )enter the vessel after passing` through a part of thefurnace. Out of the ends of these pipes the water is forced into thesuperheated steam in the generator A. The length 191919191919 in thefurnace should be such as to afford timefor the heat passing over thepipe to raise the temperature of the water in it nearly to thetemperature of the superheated steam in the vessel A. Under thesecircumstances the entering Water, regulated in quantity by the engineer,is converted into superheated steam immediately.

C C C", Figs. 5 and 6, are pipes which (in combination represented inFigs. 5 and 6) enter the plate which closes the vessel A. They are innumber such that each stream-or jet is small, or the waterissues fromthe ends through orifices that produce jets adequately small. Waterforced by the action of the injector through these orifices willpenetrate the superheated steam and, being regulated in quantity by theengineer, will be converted into superheated steam.

G is aGifiard injector or some form of forcepump by means of which wateris forced through the pipe or coil C. A branch, M, from this pipe leadsto the water-reservoir, and by means of a cock, L, on it such part ofthe water delivered by the injector or force-pump is thrown back intothe reservoir as may be found advisable. y

D is a discharge-pipe which extends to near the bottom of the vessel A,by means of which any accumulation of water is blown out when desired.

S is a steam-pipe which conveys the superl heated steam from the vesselA to the place and parts where it is to be used.

In the use of these combinations their satisfactory operation willdepend on the proper adjustment of the supply of water oy pipes C O' C,to the state of the fires, and the rate at which superheated steam istaken away by pipes. 1t will be seen that in either case it is notintended that water be injected onto the surface of the vessel, but thatthe volume of superheated steam 7 is the material (so to designate it)which receives the entering jets and supplies, as far as any additionalheat is necessary, the heat which converts the entering water intosuperheated steam. It is this part of the combination and its operationwhich distin guishes it from attempts to make steam continuously andsatisfactorily by injecting water on the inner surfaces of heatedvessels. rIhe hot surface of the vessel was the part provided to convertthe water thrown upon it in spray or jets into steam. Various as theseattempts have been, they have all had this common feature-viz., that thehot surface was to receive the water, whereas in my combination I takespecial care to provide such depth of volume of superheated steam toreceive the water as will cause the water to pass into a state ofsuperheated steam before it reaches the sura face. And it is in thisfeature that we find explanation of the fact that my invention, hav ingbeen thoroughly tried, is perfectly successl yful, working with aregularity, steadiness, an

practical character which leaves nothing to be desired, except aknowledge of the durability of the vessel used under such circumstances.

Three elements enter into the production of superheated steam by the useof these combi nations, viz: First, surface of generator exposed to theaction of re and heat; second, cubic contents of generator, whichydetermines the volume of superheated steam which provides the heat bywhich the entering water is converted into superheated steam third,quani tity of water forced into the superheated steam in a given time. j

It will be seen that with any vessel of known cubic content and surfacethere is a certainquantity of water which, with that cubic con= tent ofsuperheated steam and surface, under the action of a certain amountofheat, will be continuously and satisfactorily converted intosuperheated steam; and therefore it will be seen that by regulating thequantity of water entering, vessels of any relative surface and contentcan beus'ed, and as the quantity of Water is a matter of regulation itis only necessary to provide ample means of supply and regulation,leaving to the engineer the adapta tion of these means to the proportionof the other elements. Continued use of these com- 'binations willdefine, as cannot be done be forehand, the exact quantity of Water whichshould beinjected under known circumstances.

In practice it has been found that a spherical vessel (same asrepresented inthe drawings annexed) of thirty inches internal diameter,placed in a furnace having three square feet i of grate-surface, intowhich vessel, when lilled with superheated steam of one hundred to onehundred and twenty pounds pressure, and 500O-to 60()O temperature, therewas supplied twelve cubic inches of water per minute through about fortyorifices of about one-tenth of an inch diameter, ran an engine having acylinder five inches diameter, eightinches stroke, atapressure of eightypounds per square inch, and two hundred revolutions per minute.

In determining the plan and proportions of the elements of thesecombinations it is to be remarked ,for the guidance of those interested,first, that a body of superheated steam of 500'o to 6000 temperature,and one hundred and twenty to one hundred and fifty pounds pressure is adensity, and heat not readily penetrated by jets of water Without acommunication of heat that will convert the water into superheatedsteam, but that, second, it is advisable to have a considerable depth ofsuperheated steam in advance oi' the entering jets, and that it is notadvisable to have less than ten inches, though less depth would answerwith less efficiency; third, that oritces of OnesiXteenth t0 one-eighthof an inch diameter permit jets which operate well in practice.

The form of vessel or generator represented in the drawings isspherical, selected as the one of greatest strength and capacity Withagiven amount of material; but any form of vessel of adequate thicknessot' parts in relation to its form and sustained pressure can be used.

To secure the mostefcient generator with given Weight of parts, regardmust be had to the practical suggestions herein contained.

What I claim as my invention, and desire to secure by Letters Patent,is-

The combination of the heated generator A, filled with superheatedsteam, With Water-injecting pipe C or C or G, and force-pump G, when soadjusted that Water injected into the superhcated steam in quantityregulated to the action of the lire, and surface, and content ofthegeneratoris immediately converted into superheated steam, allsubstantially as herein described.

To the above specification of my superheatedsteam generator I havesigned my hand this 25th day of September, 1865.

EBENEZER DANFORD.

Witnesses:

EDWARD H. KNIGHT, W. F. HALL.

